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81.
The methodologies used for cytometric sorting of fresh spermatozoa never allowed a clear resolution of sexual chromosomes of frozen-thawed semen. To devise a novel method for the production of bovine predefined sexed embryos using frozen-thawed semen, sorting efficiency of different protocols was studied using a new quantitative real-time PCR method to verify the purity of sexed semen. To this aim, after Percoll separation, frozen-thawed samples were stained at different temperatures and concentrations of Hoechst 33342 using a short-incubation time. The concentration of Hoechst 33342 of 500 mug/ml at a temperature of 37 degrees C provided good and stable fluorescence signals. Preventing the sperm clustering by adding 0.6% BSA in the 90% Percoll fraction led to X-bearing sperms purity of 91+/-2%. Thereafter, sorted sperms were used for in vitro fertilisation (IVF). Despite the lower cleavage rates reported in the sorted groups when compared with the control groups (40 vs 48%, P<0.01), blastocyst formation in the sorted and control groups was not different (27 vs 24% of the cleaved respectively). The PCR analysis of 30 blastocysts confirmed 26 embryos to be correctly sexed (87%). Transfer of two embryos per recipient into six synchronised heifers resulted in four pregnancies. Two abortions occurred at day 60, while two pregnancies went to term delivering two female calves. In conclusion, high purity and repeatability of sorting was obtained with frozen-thawed bull semen that was subsequently used for IVF giving rise to viable embryos and offspring. In addition, real-time PCR revealed to be an optimal support for these studies, providing a rapid and reliable estimation of flow cytometric efficiency.  相似文献   
82.
International Journal of Information Security - Cardiac implantable electronic devices (CIED) are vulnerable to radio frequency (RF) cyber-attacks. Besides, CIED communicate with medical equipment...  相似文献   
83.
Clean Technologies and Environmental Policy - This paper examines the net environmental impact for the Fuel Cell Electric Vehicle, in special the Solid Oxide Fuel Cell Electric Vehicle (SOFCEV), by...  相似文献   
84.
Common bean (Phaseolus vulgaris L.) seeds are an economical protein source rich in bioactive compounds with antioxidant activity. In this work, we evaluated processed seeds from two common bean cultivars regarding protein profile and antioxidant capacity before and after enzymatic digestion in vitro. We provided protein maps by two-dimensional electrophoresis (2-DE) of seeds germinated during 36 h and 72 h. The principal component analysis (PCA) showed that protein abundance had more variation on germination times than the cultivar ones. Seeds germinated for 36 h showed greater antioxidant capacity compared to germination for 72 h and cooking, before and after enzymatic digestion. In protein isolates, cooking associated with digestion provided better antioxidant capacity. Germination time influences protein expression as well as the antioxidant capacity of common beans. Furthermore, in vitro digestion increases the antioxidant capacity of cooked bean protein isolates.  相似文献   
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86.
Ayat  Maha  Kechouane  Mohamed  Yaddadene  Chafiaa  Berouaken  Malika  Ayouz  Katia  Boarino  Luca  Gabouze  Noureddine 《SILICON》2019,11(6):2669-2674
Silicon - Porous silicon (PSi) structures with strong hydrophobicity have been achieved by chemical etching of p-type silicon substrates in a solution based on hydrofluoric acid solution (HF) and...  相似文献   
87.
Primary plasma cell leukemia (pPCL) is a rare and aggressive variant of multiple myeloma (MM) which may represent a valid model for high-risk MM. This disease is associated with a very poor prognosis, and unfortunately, it has not significantly improved during the last three decades. New high-throughput technologies have allowed a better understanding of the molecular basis of this disease and moved toward risk stratification, providing insights for targeted therapy studies. This knowledge, added to the pharmacogenetic profile of new and old agents in the analysis of efficacy and safety, could contribute to help clinical decisions move toward a precision medicine and a better clinical outcome for these patients. In this review, we describe the available literature concerning the genomic characterization and pharmacogenetics of plasma cell leukemia (PCL).  相似文献   
88.
We previously reported that c-KIT+ human amniotic-fluid derived stem cells obtained from leftover samples of routine II trimester prenatal diagnosis (fetal hAFS) are endowed with regenerative paracrine potential driving pro-survival, anti-fibrotic and proliferative effects. hAFS may also be isolated from III trimester clinical waste samples during scheduled C-sections (perinatal hAFS), thus offering a more easily accessible alternative when compared to fetal hAFS. Nonetheless, little is known about the paracrine profile of perinatal hAFS. Here we provide a detailed characterization of the hAFS total secretome (i.e., the entirety of soluble paracrine factors released by cells in the conditioned medium, hAFS-CM) and the extracellular vesicles (hAFS-EVs) within it, from II trimester fetal- versus III trimester perinatal cells. Fetal- and perinatal hAFS were characterized and subject to hypoxic preconditioning to enhance their paracrine potential. hAFS-CM and hAFS-EV formulations were analyzed for protein and chemokine/cytokine content, and the EV cargo was further investigated by RNA sequencing. The phenotype of fetal- and perinatal hAFS, along with their corresponding secretome formulations, overlapped; yet, fetal hAFS showed immature oxidative phosphorylation activity when compared to perinatal ones. The profiling of their paracrine cargo revealed some differences according to gestational stage and hypoxic preconditioning. Both cell sources provided formulations enriched with neurotrophic, immunomodulatory, anti-fibrotic and endothelial stimulating factors, and the immature fetal hAFS secretome was defined by a more pronounced pro-vasculogenic, regenerative, pro-resolving and anti-aging profile. Small RNA profiling showed microRNA enrichment in both fetal- and perinatal hAFS-EV cargo, with a stably- expressed pro-resolving core as a reference molecular signature. Here we confirm that hAFS represents an appealing source of regenerative paracrine factors; the selection of either fetal or perinatal hAFS secretome formulations for future paracrine therapy should be evaluated considering the specific clinical scenario.  相似文献   
89.
The structural diversity of terpenes is particularly notable and many studies are carried out to increase it further. In the terpene biosynthetic pathway this diversity is accessible from only two common precursors, i. e. isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP). Methods recently developed (e. g. the Terpene Mini Path) have allowed DMAPP and IPP to be obtained from a two-step enzymatic conversion of industrially available isopentenol (IOH) and dimethylallyl alcohol (DMAOH) into their corresponding diphosphates. Easily available IOH and DMAOH analogues then offer quick access to modified terpenoids thus avoiding the tedious chemical synthesis of unnatural diphosphates. The aim of this minireview is to cover the literature devoted to the use of these analogues for widening the accessible terpene chemical space.  相似文献   
90.
A one-dimensional mathematical model of particulate solids thermal treatment in a fluidized bed based on the theory of Markov chains is proposed. A feature of the model takes into account the variation of particle properties that takes place during the fluidization. This variation occurs due to thermo-physical and chemical processes that take place during particulate solids treatment in the fluidized bed. These variations affect the particle settling velocity which is the main parameter that forms the bed expansion and local velocity of flow around the particles that strongly influences the thermo-physical and chemical processes in the bed. A generalized correlation for the drag force coefficient is proposed and tested for various materials. It was necessary to have more precise calculation of the particle settling velocity in the model. The model was developed to describe the drying process in the bed. A good correlation between computed and experimental data was achieved.  相似文献   
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